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HD8 Carb Repair

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Patrick67BJ8

Patrick67BJ8

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I have a set of HD8 carbs I acquired that had sat for several years and they have a couple of frozen parts I’m trying to get loose to repair. The fuel bowl cover bolts broke off and I’m not sure how to remove the center post that the covers bolt attached too. Any advice? They’ve been soaking in penetrating oil for a few weeks now.
Thanks
 

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Very direct heat and some vice grips . Heat it quickly but dont burn the aluminum then grab it with the vice grips and wiggle it dont just try to undo it . One it’s moving then unscrew it .
 
Suggest asking Joe Curto if they can be fixed. The studs may be cast in place.

The float bowls are identical to those on the HD6, so one should be able to source used from Joe, Healey Surgeons or Brit Car Specialists.
 
steveg said:
Suggest asking Joe Curto if they can be fixed. The studs may be cast in place.

Also, the float bowls are identical to those on the HD6, so you should be able to source used from one of the usual sources.
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Cast in place ? The stud is steel the bowl is aluminum.
 
HN,

I'm not suggesting the stud is aluminum.

Here's why I'm saying the steel stud is cast in place in the aluminum:

This is a mirror view of the stud in one of my spare HD series bowls. If it were threaded, at least one thread would be visible here. Also, if it were threaded, folks would be pulling them out of the aluminum and ruining the float bowls, as those threads would be weaker than the big nut and steel threads at the top. Not to mention the process of drilling, tapping and inserting the threaded stud would be more expensive.

If it were replaceable, of course Burlen et al would have a part number for it. Even if it was no longer stocked.



screenshot.2095.jpg
 
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Even if the studs were threaded, the threads would likely be Whitworth. The cover nuts are. Replacement bowls and cover nuts are required.
 
Healey Nut said:
...comment deleted...
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...text deleted...

I went out to my shop and cut up a perfectly good float bowl to prove his [steveg's] point. I did not for a minute think he thought there was an aluminum stud (he is waaaay sharper than that)..... But apparently you have never run across steel studs "cast-in-place" in aluminum castings, I have.

Here are some pictures, there is a very large knurl on the bottom of the stud where it is cast into the aluminum - this is often done where there is a strong desire to NOT have the stud unscrew (loosen) in its service life.
IMG_3029.jpgIMG_3033.jpgIMG_3035.jpg


Dave
 
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Dave,
Sectioning a bowl is waaaaay above and beyond the call of duty!

This is a valuable contribution. I'd imagined some kind of flange, like a nail head. The knurling is interesting in that when the nut is tightened, the slanted edges of the knurl press outward, compressing the aluminum. This is playing to strength in compression. If there were a flange, that would be shear, where aluminum is weak.

Another cool little item of respect for the designers of these very simple but very effective carburetors.

I write this as a former Weber-carbureted Alfa owner appreciating both ends of the complexity spectrum.
 
Dandare said:
Red Dave, I was going to make you an offer for that float chamber!

Can you fix it?

Danny
Click to expand...

Danny,
The bowls are available from Burlen: LH is AUC 2067; RH is AUC 2062

Not sure if you have used parts available from Healey Factory or other Aussie suppliers.

Edit: I get it - bada bing!
 
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Thanks to all who have responded to my post. It’s been both educational and entertaining.

I now believe it was installed in a way that it can’t be removed. However, I would like to check with Joe Curto and post his response for all to see.

A big thanks to Red57 for going above and beyond the call of duty!

Thank you!
 
Patrick67BJ8 said:
Thanks to all who have responded to my post. It’s been both educational and entertaining.

I now believe it was installed in a way that it can’t be removed. However, I would like to check with Joe Curto and post his response for all to see.

A big thanks to Red57 for going above and beyond the call of duty!

Thank you!
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I just talked to Joe Curto and he said he repairs them!

I have to cut off the damaged stem as close to the bottom of the bowl and send it to him. He recommended a Dremel Tool for the job and I have that. He has a special tool to remove whats left of the old stem and he then taps the hole and puts a new stem in that he has made for the job. Price: $30.00 He did say that if I couldn't cut the stem off he would have to charge extra. He also cautioned me to be careful of the aluminum near the stud.
Sounds like a reasonable charge for the repair.
 
steveg said:
Patrick,
Thank you for following up with Curto and posting this valuable info.
Click to expand...

You're welcome Steve!

I’ll be sending them to Joe as soon as I cut the stems off and post photos of the results after Joe sends them back to me.
 
Patrick67BJ8 said:
You're welcome Steve!

I’ll be sending them to Joe as soon as I cut the stems off and post photos of the results after Joe sends them back to me.
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I sent them to Joe and upon dismantle the fuel bowls were toast and couldn’t be saved. What they do if they’re still good would be to cut the stem off close to the point where it’s inserted and then drill that out and tap it. Then screw in a replacement stud.
 
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